The International Association for Comparative Research on Leukemia and Related Diseases (IACRLRD) with secretariat officers at the Harvard School of Public Health, Department of Cancer Biology is requesting financial support from the National Cancer Institute for its XIX International Symposium for Comparative Research on Leukemia and Related Diseases. These symposia are held every two years. The XIX Symposium will be held at the Congress Center Mannheim Rosegarten in Mannheim, Heidelberg, Germany with Professor Rudiger Helhmann, President of the IACRLRD, serving as host and conference co-chair. Funds are requested for the travel, meeting expenses, and registration fees of invited speakers, session chairpersons, and moderators from the United States. No funds are requested for meeting personnel. The focus of the XIX Symposium will be on molecular aspects of pathogenesis and treatment of leukemia and lymphoma as well as genetic predisposition and prevention. Progress to date in man and animals will be emphasized as well as challenges an opportunities for the future. The symposium will consist of four plenary sessions, six mini-symposia sessions, three short oral presentation sessions, numerous poster presentations and five special lectures as well as several satellite sessions. The program will also include sessions on progress in comparative research in leukemia, lymphoma, and AIDS related malignancies in the fields of cell biology, molecular biology, genetics, virology, immunology, chemical and biologic leukemogenesis, epidemiology, and therapy. The four two-hour plenary sessions will include overviews and in- depth updates of selected topics in each field to be presented. Conjoint poster sessions will supplement the plenary sessions to provide detailed coverage of members' research projects. Comparative aspects of mammalian leukemogenesis will also be emphasized. Along with sessions on molecular mechanisms and therapy, emphasis will be given to gene therapy opportunities, prion diseases, retrovirology, immunodeficiencies, cell signalling, genetic predisposition, and stem cell manipulations. The Symposium will be of interest to molecular and cellular biologists, cancer researchers virologists, hematologist, immunologists, and clinicians caring for patients with leukemia. The format will include invited plenary speakers, proffered papers, and abstract presentations. Ample time will be available for informal interaction and discussion. Attendance will be limited to 600 registrants.